Risk Factors for Reintervention With Functionally Single-Ventricle Disease Undergoing Staged Palliation in England and Wales: A Retrospective Cohort Study

ur study aimed to evaluate population-based rates of, and risk factors for, cardiac reinterven-tions in children with functionally single-ventricle (f-SV) congenital heart disease. A retrospective cohort study was undertaken, including all children born in England and Wales with f-SV congenital heart disease 1 between 2000 and 2018 who underwent any initial or staged palliative procedures. 1,2 The National Congenital Heart Diseases Audit (registry) was used, with National Health Service Research Ethics Committee approval; the study dataset is available only on this basis. Five-year survival, as ascertained in 2020, was 72.1% (95% CI, 70.6%–73.7%). 1 The study outcome was any cardiac operation or interventional catheter undertaken in addition to the planned treatment pathway. The association between prespecified risk factors (see Table) and the cumulative incidence of additional procedures was investigated using multivariable Fine-Gray regression. Competing events were death and next staged treat-ment completion or heart transplant without additional procedures. Among 3307 children with


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ur study aimed to evaluate population-based rates of, and risk factors for, cardiac reinterventions in children with functionally single-ventricle (f-SV) congenital heart disease.A retrospective cohort study was undertaken, including all children born in England and Wales with f-SV congenital heart disease 1 between 2000 and 2018 who underwent any initial or staged palliative procedures. 1,2The National Congenital Heart Diseases Audit (registry) was used, with National Health Service Research Ethics Committee approval; the study dataset is available only on this basis.Five-year survival, as ascertained in 2020, was 72.1% (95% CI, 70.6%-73.7%). 1 The study outcome was any cardiac operation or interventional catheter undertaken in addition to the planned treatment pathway.The association between prespecified risk factors (see Table ) and the cumulative incidence of additional procedures was investigated using multivariable Fine-Gray regression.Competing events were death and next staged treatment completion or heart transplant without additional procedures.
We identified the following cardiac procedures as on the planned treatment pathway  We performed 6 models (2 intervention types ×3 surgical stages) to investigate the relationship between the cumulative incidence of additional procedures and risk factors.In each model, only those patients who completed the staged procedure were included.The most common concurrent procedure was pulmonary arterioplasty at all 3 stages.The most common additional procedures were (1) stage 1 to next staged treatment: redo systemic-to-pulmonary arterial shunt (surgery, 4.1%) and balloon dilation of aortic re-coarctation (catheter, 5.4%); (2) stage 2 to 3: operative pulmonary arterial repair (1.2%) and transcatheter pulmonary artery stenting (5.5%); (3) post-stage 3: operative pacemaker placement (2%) and transcatheter Fontan fenestration closure (7.9%).Significance level (P value): *0.05, **0.01, ***0.001.N/A indicates not available; and Ref., reference.
†In the post-stage 3 analysis, we censored patients who underwent competing events due to limited sample size (death or heart transplant after Fontan without additional surgeries 3.0% and catheter interventions 2.3%).We used a conventional multivariable Cox regression model and presented the adjusted cause-specific hazard ratio as the results.
‡Low weight includes imputed data in 64 patients (2.1%).§Not included due to nonoccurrence.‖Externally validated national capture of all cardiac procedures for National Audit in England and Wales occurred from the year 2000, but procedures for capture of noncardiac variables were improved from 2009; hence, we added an era variable (born after vs before 2009) to the models.616 [25.3%]); and after stage 3 (135 [8.5%] and 387 [24.3%]).
Between stage 1 and the next stage that occurred, all stage 1 subtypes were associated with higher risk of additional surgery, compared with the reference category of Norwood, most notably hybrid (adjusted subdistribution hazard ratio, 3.45 [95% CI, 2.56-4.65];P<0.001).The hybrid was also associated with higher risk of additional catheter intervention after stage 1 (2.84 [2.13-3.79];P<0.001); and between stages 2 and 3 (1.83[1.14-2.93];P<0.05).Nonhybrid stage 1 subtypes were all associated with lower risk than the Norwood, of additional catheter procedures at later stages.
Increased severity of illness (ie, ventilation, shock) before the first procedure was associated with higher risk of additional surgery after stage 1 (1.50 [1.19-1.89Parents and clinicians should be prepared for additional procedures in the early years for most children with f-SV disease.Although it is infeasible to adjust for all aspects of case complexity, additional procedures could represent a disadvantage of the hybrid pathway.As previously reported, 4,5 the pulmonary arteries most often require additional interventions in f-SV, especially transcatheter beyond stage 2. Strategies to minimize pulmonary arterial distortion, preserve ventricular function, and maintain lower pulmonary vascular resistance may protect children from additional procedures during childhood.